Material drier



Sept. 22, 1925.

E. W. SPRAGUE MATERIAL DRIER Filed Aug. 25, 1924 3 Sheets-Sheet Sept.22, 1925. 1,554,239

E. W. SPRAGUE MATERIAL DRIER Filed Aug. 25, 192.4 3 Sheets-Sheet 2S14/nemici sept. 22, 1925. 1,554,239l

E. W. SPRAGUE MATERIAL DRIER Filed Aug. 25, 1924 5 Sheets-Sheet 3Patented Sept. 22, 1925.

EDWARD 'W. SPRGUE, OF ALLEN TOWN, PENNSYLVANIA.

MATERIAL DRIER.

Application led August 25, 1924. Serial No. 733,865.

To all 'whom it may concern:

Be it known that I, EDWARD W. SPRAGUE, a citizen of the United States,and resident of Allentown, Lehigh County, State of Pennsylvania, haveinvented certain new and useful Improvements in Material Driers, ofwhich the following is a specification.

The invention relates to material driers whereby various materials suchas coal and e various other kinds of material in bulk containing wateror other liquid to be removed therefrom, may be efliciently dried.

An object of the invention is the provision of an effective andcomparatively simple form of apparatus vwhereby coal and other materialsmay be continuously dried in a thorough and efficient manner, theapparatus being reliable in operation andV comparatively simple inconstruction. According to lthe invention the material is forced to passover one-.plate or platform after another, in aA descending series, thematerial' being turned over and exposed tothe air or heating gas duringits passage. invention consists in the manner in which hot .gas or airis used in the drying process.

According to the preferred vform vof the invention, the gas is firstcaused to pass beneath the first plate of .the series on which thelmaterial containing the largest quantity of moisture is exposed. Thehot gases then pass `successively beneath the remaining ylates `indescending order. The gases, whic have meanwhile lost a good deal .oftheir heat, ynow pass upwardly over the surfaces of the plates andthrough the material thereon in ascending order. By this means the'dryi-ng heat is used most effectively and with the least danger ofburning or otherwise injuring the material or the apparatus.

Also in the preferred form of the invention the material is'fed upon astepped rotating plate. It travels about upon the upper and outermoststep ofthe plate for a suitable interval until it encounters astationary member which pushes it down onto the next lower plate andsomewhat 4turns it over in so doing. The materialthus is fed radiallyinwards over the plate untilit reaches the central part thereof when itdrops on toa lower plate, upon which it rotatesand on which it is fedradially outwards in the same .mannelg the material then dropping on tothe outer edge of the next lower stepped e plate,- after which theoperation described above is repeated.

A feature of the.

The invention consists in improved apparatus of the character referredto and the various combinations of elements and con structural formsthereof, as will appear more fully from the following specification andwill be more particularly pointed out in the appended claims.

In order that the invention may be more clearly understood, attention ishereby directed to the accompanying drawings form.- ing apart of thisapplication and illustrating one form of the invention. In the drawings,

Fig'. 1 is a vertical section through the ap- Y paratus taken on line 11 of Fig. 2. Fig. 2 1s a top plan view of the apparatus and Figs. 3, 4and 5 are'respectively horizontal sections taken on lines 3 3, 4 4 an'd5-5 -of Fig. 1.

Referring to the drawings the material to 'be dried is placed in a binor hopper 1 from the bottom of which it is to be moved or conveyed tothe drier. A feeder or conveying device 2 is indicated in the drawings,which may be of any suitable character. As'shown this may be for examplean endless pusher or conveyor belt, a roller of which is rotated bymeans of horizontal shaft 3 which is driven by bevelgears 4 and 5 from avertical shaft 6. Shaft 6 is driven by bevel gears 7 and 8 from ahorizontal shaft 9 at the bottom of the drier which shaft is rotatedinany 'desired manner as by means ofthe motor 10, which may rotate shaft9 at a re- (lluced' speed through reduction gears 11 and The dryingapparatus is shown as enclosed within a suitable wall 13 which may vbecylindrical in shape as illustrated, the vertical shaft 6 extendingcentrally through the same. The various rotating plates or platterialtobe handled. The plate. has a cir-v cular central opening therethroughbounded by the annular vertical flange 16 of the plate to which flangethe arms of the supporting spider 15 may be secured. The flange `1 6 ofplate14'rotates within an annular flange 17 of the stationary plate 18which is supported next lower drying chamber.

in wall 13 of the drier beneath spider 15. rlhe upper and outermost stepof plate 14 is preferably provided with a pair of annular upwardlyextending flanges 19 which co-act with the downwardly extending flanges20 of a cover plate 21 secure-dto the upper edge of wall 13, to form anedge seal for the rotating plate.

The material to be dried falls from conveyor or feeder 2 upon theoutermost step of drier plate 14 and the material travels around uponthis outermost step for a distance which maybe nearly a completerevolution, when it engages the outermost deflector 22 by which it isdeflected downwardly on to the next lower step. The deflectors 22 may becarried by an arm 23 secured to the cover plate 21. Y

The deflectors 22 are preferably of what may be termed a plough shape,one of the same being provided to co-act witheach step ofthe plate overwhich the material is moved. These deflectors are so shaped and arrangedthat the material will travel around on each step of the plate foralmost a complete revo lution before it encounters one of the stationary defiectors, by which it is deflected radially onto the nextlower and inner step. A suitable arrangement of the deflectors and thearm 23 therefor is indicated in Fig. 4. These ploughs or deflectors areeach pro vided with a more or less spiral twist so that the materialwill be turned over to a considerable extent as it is fed inwardly fromstep to step, -so that fresh surfaces of the material will be exposed tothe hot gases pass'- over the same and fresh surfaces will be brought incontact with the plate surfaces which as stated are heated from beneath.

The material is deflected bythe innermost deflector through the centralopening of plate 14 through which it falls upon a rotating plate 24,which may be a` plane circular horizontal plate secured to the shaft 6in the The material travels around upon plate 24 and is fed radiallyoutwardsV over the same by deflectors 25 which extend downwardly from asupporting arm 26 secured to the lower surface of the fixed plate 18.These deflectors operate in the same manner asdeflectors 22 except thatthey feed the material radially outwards instead of inwards, thematerial finally dropping over the outer edge of plate 24 onto theoutermost step of the next lower stepped plate 27.

Plate 27 is similar to plate 14 and is supported from rotating shaft 6by a spider 15 in the same manner. The material is fed inwardly, downthe steps of plate 27 by means of deflectors 22 in exactly the same.manner as has been described in connection with the movement of thematerial over plate 14, deflectors 22 being carried by an arm 23 whichmay be secured at its` upper and outer end to fixed plate 18 and at itslower and inner end to a bearing 28 surrounding Shaft 6.

The material then falls through a central opening in plate 27 and acorresponding opening in the fixed plate 30 beneath the same, plate 30having an upstanding annular fiange 29 within which rotates the bottomannular flange of plate 27 in the same manner as has been described inconnection with plate 14. The material then falls upon rotatinghorizontal plate 24in the next, or lowest, drying chamber. The materialis fed outwards over this horizontal plate by means of deflectors 25 inthe same manner as has been described in connection with the seconddrying chamber. The material falls .from the outer edge of this plate onto the lowermost step of the stepped plate 31 which is secured to shaft6 and operates in the same manner as the upper stepped plates. Thematerial is fed inwardly over the stepped plates by the deflectors 222in the same manner as has been described and falls through the centralopening in the lowermost fixed plate 32, After following through thisopening it is received upon the horizontal rotating plate 33 and ismoved outwardly thereover by deflectors 252 into the chute 34 by whichit is delivered at a desired point.

The ploughs or deflectors 22, 22 and 222 and also 25, 25 etc. Yare soarranged that the entire surfaces of plates 14, 24, 27 ,24, and 31 arekept uniformly covered with the material which is being dried. A threechamber l drier is illustrated but it will, of course, be understoodthat the number of chambers and drying and material-feeding plates maybe varied to suit material conditions.

The fiow of the hot drying gases will now be described. The hot gasesare generated within or are brought into chamber 35 which may be formedin an extension 13 of the wall of the drier. The heat may be generatedfor example by the combustion of pulverized fuel which falls intochamber 35 from a hopper 36.

The hot gases are drawn from the uppermost portion of chamber 35 intothe u )permost heating chamber 37, under and in irect contact with theuppermost revolving plate 14. The gases are carried almost completelyaround circular chamber 37 until they are deflected by means of a bafflewall 38 and pass into the vertical by-pass chamber 39 from which theypass into circular chamber 40 underneath the second revolving steppedplate 27. The hot gases pass almost entirely around chamber 40' underand in direct contact with the bottom ofr revolving plate 27 until theyare deflected by baflie wall 41 and pass'through by-pass 42 into thechamber 43 beneath the bottom stepped rotating plate 31.

-'The gasesI pass almost entirely around chamber l3-beneath and indirect contacty with plate 31 until they encounter baffle wall 44 andare drawn through opening 45 in plate 32 into chamber 46, the gases atthis time having greatly reduced temperatures.

In chamber 46 the gases for the first time come into direct contact withthe material being dried, this being the material which is about to bedelivered from the drier. The hot gases in chamber 46 are then drawnupwardly through the central opening 47 in plate 32, between the arms ofthe spider 152 of stepped plate 31. The hot gases pass upwardly throughthe material which is descending through this opening and through andover the material which is rotating upon plate 31. The gases aredeflected by the bottom surface of horizontal plate l24', which theywill heat in passing. They pass around plate 24 and thence up throughthe openings between spider arms 1,5. The gases then pass through andover the material on stepped plate 27, and are deflected by p-late 24,pass around the same and through the central opening in stepped plate 14and through and over the material on plate 14. The gases are then drawnthrough a conduit 48 which extends up from cover plate 21 of the drierto an exhaust fan 49 which may be operated by a motor 50. This fansupplies the induced draft to draw the gases from the furnace or heatchamber successively through the various chambers and passageways asdescribed. From the exhaust fan 49 the gases may be forced into thecyclone 51 which may be used for recovery of particles of material drawnfrom the drier.

The gases are then forced from this cyclone or settling chamber into aWasher 52 and thence through pipe 53 to the atmosphere.

The hot gases preferably pass around through the various chambers 37,and 43 in reversed directions. That is to say the gases may' pass aroundchamber 37 in a clockwise direction as indicated in Fig. 3 and thenaroundfchamber 40 in a counterclockwise direction as 'shown in Fig. 4and y then around through chamber 43 again in a clockwise direction 'asshown in Fig. 5. By the heat circulation system described, it will benoted, the heat is first applied indirectly to the material, through thedrying plates r 14, 2.7v and 31, the amount 'of heat supplied4decreasing correspondingly as the moisture content of the materialdecreases from one plate to the next. The heat of reduced temperature isthen caused to act directly upon and through the material bein dried asit is caused to pass through and a ut the material itself in the mannerdescribed. Accordingly the heat is used in an exceedingly efficientmanner to dry the material most effectively and Without danger orinjury.

It should be understood that the invention is not limited strictly t0the exact details which have been described, but the same is as broad asis indicated by the accompanying claims.

I claim:

1. In a drier, the combination of a plurality of superposed plates,means for revolving the same, means for moving material over each ofsaid Iplates in succession, from top to bottom, and conduit and bafilemeans for causing hot gas to pass under said plates in'succession, fromtop to'bottom, andv then to pass over said plates and over and throughthe material thereon, from bottom to top.

2. In a drier, the combination of a series of drying chambers, means forprogressing material through thek same in order, and conduit and bafflemeans for causing hotl gas to pass in contact with walls of saidchambers in the same order in which material passes through the same.

3. In a drier, the combination of a series of plates, means for feedingmaterial over the same, `:in order, and conduit and baffle ineans'forcausing hot gas to pass successively in contact with the lower surfacesof said plates, in the same order in which. ma-

terial'passes over the same.

4. In a drier, the combination of a series of chambers, means forprogressing material through the' same successively, means affordingpassages adjacent to said chambers for causingl hot gas to first heatsaid chambers through Walls thereof, successively, and means comprisingpassages connecting said chambers adapted to then pass the gas throughthe chambers in direct contact with thel material therein.

5. In a drier, the combination of a seriesl of plates, in descendingorder, means for feeding material over the same successively,`

in descending order, and means affording passages for causing hot gas topass under the plates successively, from the upper to the lowermost.

6. In a drier, the combination of a series` of plates, in descendingorder, means for feeding material over the same successively, indescending order, means comprising chambers with connecting passages forcausing hot gas to pass under the pilates successively, from the upperto the lowermost, and means affording passages. to then pass the gasabove the plates, in contact with the material thereon, in ascendingorder.

7. In a drier, the combination of a rotating vertical shaft, a plate ofgenerallyconical shape thereon, formed of annular horizontal steps, saidplate having a delivery opening at the center, means for feedingmaterial on to the outermost step, and fixed means for transferring thematerial from each higher to the next lower step after a period ofrotationfthereon. d

8. In a drier, the combination of a vertical `sha-ft, a plate formedofannular steps of descending height secured thereon, means for feedingmaterial on to the upper step, and means operative each revolution totransfer the material successively from each step to the next lowerstep. I

9. In a drier, the combination of a rotating vertical shaft, a series ofplates secured thereon, at intervals, 'one above another, alternateplates having central openings therethrough, means for feeding materialonto the uppermost plate, and fixed deflectors arranged to transfer thematerial inwardly, step by step, after rotation on annular portions ofeach of said plates having central openings, and to similarly transferthe material outwardly on the other plates,said latter plates beingarranged to deliver the material over the edges thereof on to the platesbelow.

10. In a drier, the combination of a vertical shaft, superposed dryingplates thereon, transfer devices between each two plates, means forfeeding material over each of said plates to deliver it to the transferdevice below, said transfer devices delivering the Inaterial to theplates bel-ow, meansaffording passages extending under the plates forcausing hot gas to pass under each of said plates and guiding means forcausing the gas thereafter to pass adjacent to each of said transferdevices.

11. In a drier, the combination of two series of superposed plates, themembers of one being alternated with those of the other, the plates ofone series having delivery openings therethrough, means for feedingmaterial over all of said plates successively, and through saidopenings, from top to bottom, and means comprising guiding surfaces forcirculating hot gas under the plates of one series and then through saidopenings, above said plates and around said plates of the other series.

In testimony whereof I have signed my name to this specification.

.EDWARD w. SPRAGUE.

